Field
The current disclosure relates to computer networking, including, without limitation, computer networking devices configured to operate in Transparent Interconnection of Lots of Links (TRILL) compliant networks.
Background
The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
TRILL is a standardized protocol to perform bridging using IS-IS (Intermediate System to Intermediate System) link state routing. An RBridge (Routing Bridge) is a device that implements TRILL and is also known as a “Trill Switch”. An RBridge that is attached to an endnode is called an “edge RBridge”. An RBridge that exclusively forwards encapsulated frames is known as a “transit RBridge”. Conventionally, an ingress edge RBridge encapsulates a native Ethernet packet with a TRILL header, and an egress edge RBridge receives a TRILL-encapsulated packet and removes the TRILL header. To encapsulate, received packets a conventional ingress edge RBridge keeps an “endnode table” also known as a “forwarding table” that includes (Media Access Control (MAC) address, TRILL egress switch nickname) pairs, for those MAC addresses currently communicating with endnodes to which the ingress edge RBridge is attached.
If the ingress edge RBridge has many attached endnodes, the endnode table becomes extremely large. Also, if one of the MAC addresses in the table has moved to a different egress edge RBridge, it is difficult for the ingress edge RBridge to quickly notice movement. As a result traffic will get lost because the ingress edge RBridge tunnels to the incorrect egress edge RBridge.